LUNEX5 (free electron Laser Using a New accelerator for the Exploitation of X-ray radiation of 5th generation) aims at investigating the production of short, intense, and coherent pulses in the soft x-ray region. The single Free Electron Laser (FEL) line fed either by a superconducting Linear Accelerator of 400 MeV or a 0.4–1 GeV Laser Wake Field Accelerator (LWFA) enables seeding (High order Harmonic in Gas seeding and Echo Enabled Harmonic Generation) for the advanced fourth generation source with the conventional accelerator, and single spike operation for the fifth generation source with the LWFA. Two pilot user experiments for time-resolved studies of isolated species and solid state matter will take benefit of LUNEX5 FEL.

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